Originally Posted by Freebase Dali

I think the major factors are strength (I wouldn't go with anything less than 15x), medium (Water bubblers are best because they smooth the smoke and you can hold more for longer) and hold-time (A good lung-full for 15-20 seconds followed by another).

Another thing I've noticed is Salvia's potency decreases with age. I've been having the same 3gram bag for about 2 years now and it's nowhere near as potent as when I first got it.